高强度间歇训练对青年女性身体活动和身体成分影响的实验研究

An Experimental Study on the Effects of High-Intensity Interval Training on Physical Activity and Body Composition of Young Women

目的:探析高强度间歇训练(high-intensity interval training,HIIT)对青年女性身体活动(physical activity,PA)和身体成分的影响,并进一步探究HIIT对身体成分的干预效果是否受到PA影响。方法:招募62名非规律运动青年女性,随机分为HIIT组(HIIT,n=30)和对照组(CON,n=32)。HIIT组完成12周,每周3次的训练:训练目标强度为90%HRmax,每次训练中20 s功能性训练和10 s休息为1组,重复8组,共4 min。CON组不参与运动。干预前、后分别进行问卷调查、身体成分、心肺耐力和PA测试。采用配对t检验分析干预前后组内差异,采用混合线性模型分析干预前、后组间差异。对组间差异显著的结果指标构建模型,以HIIT、PA和交互项为固定效应,以个体差异为随机效应。结果:1)与CON组相比,12周干预后HIIT组体脂率和脂肪重量显著改善(P<0.001),其中,脂肪重量效应量中等(Cohen’s d=1.02),体脂率效应量大(Cohen’s d=1.25);而体重、身体质量指数、腰围和去脂体重无显著变化(P>0.05)。2)与CON组相比,12周干预后HIIT组MVPA(Cohen’s d=1.92)和TPA(Cohen’s d=1.80)显著改善(P<0.001),效应量均为大。3)HIIT对身体成分的干预效果受到PA水平变化的影响。结论:12周低运动量HIIT能够提高青年女性PA水平,改善其身体成分,且PA水平提高会影响HIIT对身体成分的干预效果。

Objective:To study the effects of high-intensity interval training(HIIT)on physical activity(PA)and body composition on young women,and to further explore whether the effects of HIIT on body composition is affected by PA.Methods:62 physical inactivity young women were recruited and randomly assigned to HIIT group(n=30)and no-exercise control group(CON,n=32).The HIIT group completed 12 weeks of training with a frequency of three times per week.The required intensity was 90%of the maximal heart rate,and each training session consisted of 8 sets of 20 s functional training followed by 10 s rest,with a total of 4 min.No exercise intervention was performed in CON group.Questionnaire survey,body composition,cardiorespiratory endurance fitness and PA measures were conducted before and after the intervention.The differences within and between groups before and after intervention were analyzed by paired t-test and mixed linear model,respectively.The mixed linear model was further constructed for the outcome indicators with significant differences between groups,with HIIT,PA and interactions as fixed effects,and individual differences as random effects.Results:1)Compared with CON group,the HIIT group experienced significant improvement in body fat percentage and fat mass after 12 weeks of intervention(P<0.001),the effect size of fat mass was moderate(Cohen’s d=1.02),and the effect size of body fat percentage was large(Cohen’s d=1.25);there were no significant changes in body weight,body mass index,waist circumference and fat-free mass(P>0.05);2)compared with the CON group,moderate-to-vigorous PA(Cohen’s d=1.92)and total PA(Cohen’s d=1.80)were significantly improved in the HIIT group after 12 weeks of intervention(P<0.001),the effect size was large;3)the effect of HIIT intervention on body composition was affect by changes in PA levels.Conclusions:12 weeks of low-volume HIIT can increase PA level and improve the body composition of young women.The PA level affects the intervention effects of HIIT on body composition.